Air springs have been used for motor vehicles and various machines and other equipment for a number of years. The springs provide cushioning between movable parts, primarily to absorb shock loads imparted thereon. The air spring usually consists of a flexible elastomeric reinforced sleeve which extends between a pair of end members. The sleeve is attached to the end members to form a pressurized chamber therein. There may be one or more pistons located within the flexible sleeve. The end members mount the air spring on spaced components or parts of the vehicle or equipment on which the air spring is to be mounted.
The internal pressurized fluid, generally air, absorbs most of the shock impressed upon or experienced by one of the spaced end members by which the air spring is mounted. The end members move inwards and towards each other and also away and outwards from each other upon absorbing the imparted shock.
To prevent the end members from contacting each other during inward movement, many prior art springs have internal bumpers mounted on one of the end members. The bumper extends into the interior of the pressurized chamber. The bumper prevents total collapse or deflection of the spring member in the event of air spring failure, and absorbs shock upon the spring experiencing severe shocks and deflections.
Examples of prior art spring bumpers include U.S. Pat. No. 3,475,015. The bumper therein is molded onto the plate.
U.S. Pat. No. 4,787,606 discloses a bumper which is pressed over a solid central post on the lower spring plate.
U.S. Pat. No. 5,201,500 discloses a bumper with fingers molded into the plastic which snaps over a mushroom head bumper nut. However, repeated and/or excessive forces may result in the bumper fingers being cracked or broken.
The disclosed invention is directed toward an improved method of mounting the air spring bumper. Greater shear strength for the bumper is realized due to the inventive securing means.